As a nonorthogonal mode, faster-than-Nyquist (FTN) signaling transmission can effectively improve the spectrum efficiency of a system. However, FTN signaling inevitably causes inter-symbol interference (ISI). The ISI hinders traditional synchronization methods from operating accurately, and this makes the carrier synchronization of FTN systems more complex. To overcome this issue, we propose an iterative carrier frequency offset (CFO) estimation scheme for an FTN signaling system. The proposed CFO estimation scheme consists of two steps: i) a coarse estimation step based on discrete Fourier transform and ii) a fine estimation step based on a golden-section search algorithm. The simulation results show that the mean square error of the proposed scheme is lower than that of the conventional CFO estimation schemes and approaches the Cramer-Rao Bound, which is an optimal estimation performance bound.

中文翻译：

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超奈奎斯特信号系统的迭代载波频偏估计方案


FTN（faster-than-Nyquist）信令传输作为一种非正交方式，可以有效提高系统的频谱效率。然而，FTN信令不可避免地会引起符号间干扰(ISI)。 ISI阻碍了传统同步方法的准确运行，这使得FTN系统的载波同步变得更加复杂。为了克服这个问题，我们提出了一种针对 FTN 信令系统的迭代载波频率偏移 (CFO) 估计方案。所提出的 CFO 估计方案由两个步骤组成：i）基于离散傅里叶变换的粗略估计步骤和 ii）基于黄金分割搜索算法的精细估计步骤。仿真结果表明，该方案的均方误差低于传统的CFO估计方案，并且接近Cramer-Rao界，这是一个最佳估计性能界。